Experimental and numerical investigation of spiral irradiating scheme for flame forming of a bowl shaped surface

Flame forming is a vastly used method for forming of ship hull plates. In this work, spiral irradiating scheme for flame forming of a bowl shaped surface is proposed and investigated both experimentally and numerically. The results of experimental and numerical investigations show that the proposed spiral irradiating scheme is a very good and suitable method for flame forming of bowl shaped surfaces. Using this irradiating scheme, an approximately symmetric bowl shaped surface is obtained. In addition, the effects of various process parameters such as pitch of spiral path, number of spiral paths, in-to-out spiral path and reversely out-to-in spiral path on the radius of curvature of bowl shaped surface are investigated. The results show that by decreasing the pitch of spiral path, symmetry of the bowl shaped surface is increased but radius of curvature does not change considerably. Also it is shown that spiral path i.e. in-to-out spiral or out-to-in does not change the radius of curvature and symmetry of bowl shaped surface noticeably. It is also concluded that the radius of curvature of bowl shaped surface can be decreased when the number of spiral paths are increased.